Field of the Invention
This invention relates to a cover for a motor vehicle roof with a cover body which is peripherally injected, especially peripherally foamed, in the area of its outside edge so as to form a plastic frame with a metal insert and a process for producing one such cover.
A cover with the above is known from published German Patent Application DE 198 08 113 A1. It is a glass composite element, especially in the form of a sliding glass roof for motor vehicles, which has a glass pane which is peripherally foamed on the outside edge with a plastic frame, preferably holding parts formed by angle sheets being peripherally foamed at the same time on two opposing sides of the glass composite element and being completely covered by the plastic frame.
The object of this invention is to devise a cover for a motor vehicle roof which, compared to the known cover, has increased torsional stiffness and a relatively small amount of foaming compound is sufficient for its manufacture. Compared to likewise known glass covers with an integral reinforcing frame, simplified production and flexible adaption to different cover dimensions and/or cover arches will be possible.
Proceeding from a cover for a motor vehicle roof with a cover body which is peripherally injected in the area of its outside edge with the formation of a plastic frame with a metal insert, and which is especially peripherally foamed, this object is achieved according to the invention by the metal insert extending frame-like along essentially the entire periphery of the cover, but being made in several parts in the peripheral direction of the cover, and the metal insert being only partially encompassed by the plastic frame.
In spite of the metal insert being composed of several parts, high torsional stiffness is obtained, because reinforcing insert parts are present not only on the side cover edges, but in practice in the entire peripheral area of the cover. Compared to an integral reinforcing frame, on the other hand, large sensitive sheet metal parts which are complex in terms of production, packaging, transport and storage are avoided. This is associated with major cost savings. Moreover, relatively simple adaption to different cover shapes and cover dimensions is possible. For example, to produce covers of the same length, but different width, identical side reinforcing parts can be used, or to produce covers of the same width, but different length, the same front and back reinforcing parts can be used. Furthermore, the only partial peripheral foaming of the metal insert generally saves expensive foam compound, and it enables lower cover weights.
Preferably, the cover is formed such that the plastic frame covers the outside edge area of the metal insert, conversely inside areas of the metal insert are left exposed.
Preferably, the metal insert has a peripheral bead, the base of which adjoins the bottom of the cover body, and the plastic frame extends to the inside as far as the outside wall of this peripheral bead.
In this case, a production process is especially suited in which, for peripheral foaming, the cover body together with the multi-part metal insert is inserted into a foaming tool and then foam compound is introduced, to limit penetration of the foaming mass to the inside, a seal being inserted into the peripheral channel of the metal insert. This seal can advantageously be reinforced in the area of the separation points between the insert parts by means of an auxiliary seal.
The metal insert is preferably divided into four parts in the peripheral direction of the cover, each insert part extending essentially along one of the four cover sides. On at least one part of the insert parts, feasibly on the side reinforcing parts facing one another, there can be cover holding devices or the like which extend downward through the plastic frame, especially holding devices for joining the cover to a cover adjustment mechanism, as is known for sliding roofs, sliding and lifting roofs and the like.
The cover body can be made especially of glass or transparent plastic. Among others, mainly PUR foam is suitable for the plastic frame.
According to another preferred embodiment of the invention, the plastic frame additionally forms side screens for covering lateral gaps between the cover and the fixed roof skin when the cover is raised.
One embodiment of the invention is explained in detail below using the accompanying drawings.